24 JULY 1847, Page 15

THICK AND THIN SOWING.

AMONG the movements of our day none strikes us as being so Impressive or so important as that which is converting agricul- ture into a science. In the discussion at Northampton philoso- phers, such as the Reverend Mr. Huxtable, were joined by prac- tical farmers, whose intelligent and animated remarks showed how thoroughly their minds have been roused. Analysis is ap- plied now, not merely to the component parts of the soil, but also to the processes of vegetation and its hinderances ; so that we are approaching the time when every process will be expounded by its rationale. It is no real ground for regret that the experiments hitherto have been mostly empirical; all inquiries are so in their early stage : but it occurs to us—speaking with deference, as mere uninitiated and admiring spectators of others' labours—that the result of inquiry might be hastened, by shaping it in some cases according to a prearranged and defined formula.

The lecture delivered by Mr. Thompson on thick and thin wheat-sowing suggests a case in point. Mr. Thompson made experiments in the comparative results of sowing wheat by broad- cast and by dibbling ; and he found, contrary to the received ex- pectation, that the produce by dibbling was far less. The plants did not come up ; and when they did, the more abundant tillering of the dibbled plants caused them to come to maturity somewhat later. On the other hand, the number of heads per plant, and the weight per ear, were greater in the dibbled plants. Mr. Thompson found that, in dibbling, the seed was often destroyed by worms ; and from all the circumstances he came to the fol- conclusions,—that thin sowing does not answer where the sal is thin ; that it does not answer where the land is ill cultivated.

Before, however, we .can be in possession of conclusions suffi- ciently generalized to afford a rationale of the relation between the depth of soil and thin or thick sowing, so as to furnish a settled guide for practice, it would seem desirable to conduct the inquiry on a. plan at once more generalized and more specific. We all perceive that vegetation depends upon due supplies to each plant or the chemical ingredients in the soil, of the water which is, as in the animal economy, the circulating medium, and of the gases supplied by the atmosphere: but what, in any case, is the due proportion between all ? It would be interesting to have re- plies to such questions as the following. Supposing that any given plant were cultivated in a climate and soil the best suited to it, what should be the quantity of soil allotted to each seed ? what should be the proportion between the cubical contents of soil $o allotted and its upper superficies ? what mode of culture results in the largest amount of produce on a given surface ? and (not strictly the converse of the last question) what is the smallest quantity of soil, in weight or inches, by which a perfect plant can be produced!